Re: Sync Rep v17

On Sat, Feb 19, 2011 at 3:28 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> First, we should be clear to explain that you are referring to the fact
> that the request
>  synchronous_commit = off
>  synchronous_replication = on
> makes no sense in the way the replication system is currently designed,
> even though it is a wish-list item to make it work in 9.2+

What exactly do you mean by "make it work"? We can either (1) wait
for the local commit and the remote commit (synchronous_commit=on,
synchronous_replication=on), (2) wait for the local commit only
(synchronous_commit=on, synchronous_replication=off), or (3) wait for
neither (synchronous_commit=off, synchronous_replication=off).
There's no fourth possible behavior, AFAICS.

The question is whether synchronous_commit=off,
synchronous_replication=on should behave like (1) or (3); AFAICS
there's no fourth possible behavior. You have it as #1; I'm arguing
it should be #3. I realize it's an arguable point; I'm just arguing
for what makes most sense to me.

--
Robert Haas
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